Male and Female Circumcision, edited by Denniston et. al
Kluwer Academic I Plenum Publishers, New York, 1999. pp. 9-18.
THE ANATOMY AND
PHYSIOLOGY OF THE
HUMAN PREPUCE
Steve Scott
INTRODUCTION
1. IN UTERO DEVELOPMENT OF THE GENITALIA
Until the seventh week of gestation, the genitalia of the embryo are
female in appearance. Around the eighth week, male hormones initiate the
development of the ma1e reproductive organs. Both male and female
genitalia evolve from the same embryonic tissue (Figure 1).
The genital tubercle becomes the glans clitoridis in the female and
the glans penis in the male. The labioscrotal swellings become the labia
majora in the female and the scrotum in the male. The urethral groove
remains open in the female, creating the vaginal orifice. Around the
fourteenth week, the urethral groove closes in the male as the urogenital
folds fuse on the ventral aspect (underside) of the penis, creating the penile
raphe. In the female, the urogenital folds become the labia minora.
In 1992, I conducted a series of interviews with physicians in Salt
Lake City, Utah. Among other questions, interviewees were asked what
knowledge they had of the nature and function of the prepuce. Aside from
the ability of a few to recite a passage from a pamphlet produced by the
American Academy of Pediatrics1 (in which the prepuce is described as
tissue that protects the glans penis), most physicians were ignorant of the
anatomy and physiology of the genital structures they were routinely
removing from infants and children. Subsequent research revealed the
reason for their lack of knowledge.
Most relevant medical texts contain no information regarding the
anatomy and physiology of the prepuce. Some do not even include the
prepuce in diagrams of the penis.2 Often, the only thing a medical student
will learn about the prepuce is the manner in which it will be excised.
Impelled by the logical premise that, if a body part exists, it may very
well serve a purpose, I began my own research. Using MEDLINE, I
collected information that identifies the prepuce as an exquisitely designed,
highly innervated and vascularised complex of specialised erogenous
structures that are vital to natural and normal sexual function. As this
information finds its way into the hands of healthcare professionals, it is
hoped that they will be able to inform parents more fully about what is lost
to circumcision.
Figure 1. Similarities in male and female genital anatomy. Adapted from Ritter TJ, Denniston GC.Say
No to Circumcision! 2nd ed. Aptos: Hourglass. 1996;11-13. Used by permission of publisher.
1.1. Development of the Male Prepuce and Frenulum
2.1. Balanopreputial Membrane
Around the twelfth week of gestation, the prepuce begins its
development as a fold of tissue originating at the coronal sulcus (the groove
that demarcates the shaft from the glans). The fold inverts (the outside
becoming the inside) as it grows forward over the glans. 3 Shared epidermal
cells of the glans and the advancing prepuce create a common
balanopreputial membrane which firmly attaches the prepuce to the glans.
The complete enfolding of the glans by the prepuce is accomplished by the
twenty-fourth week (Figure 2).
The fusion of the prepuce on the ventral aspect of the glans creates
the frenulum, a bridge-like structure that joins the ventral prepuce to the
glans.4
A common membrane binds the prepuce to the glans penis in the
fetus and neonate. This is the same binding mechanism that fuses the
eyelids of newborn kittens. This shared membrane inhibits the retraction
of the prepuce and thereby protects the developing mucosae of the
infantile glans and inner prepuce from faecal contamination.
The desquamation of this membrane, resulting in the separation of
the prepuce from the glans, is gradual and variable from individual to
individual.6 Whorls of cells form in the membrane and die from the inside
of the whorls out, creating hollows. Over time these hollows coalesce to
form the preputial space, the zone between the prepuce and the glans. 7
2.2. Preputial Musculature
One to two millimetres under the penile skin lies a smooth muscle
sheath known as the dartos fascia.8 The muscle fibres of the dartos fascia
form a mosaic pattern along the penile shaft skin and arrange themselves
in a circular sphincter-like configuration at the tip of the prepuce. 9 The
sphincteric action of this muscle can inhibit preputial retraction. This
should be seen as normal physiology rather than a pathological condition.
This sphincteric closing mechanism, beyond the urinary meatus, allows for
the passage of urine while guarding against the entrance of foreign
pathogens into the preputial space.
Figure 2. Embryological
development of the male prepuce.
2. THE EVOLUTION OF THE PREPUCE FROM
INFANCY TO MATURITY
Only 4% of newborn males have a fully retractable prepuce.s The
remaining 96% are non-retractable due to two normal physiological
conditions.
2.3. Preputial Development in Adolescence and Maturity
The tubular, tapered, and elongated prepuce of the young boy should
not be seen as "hypertrophic" or "redundant" tissue that requires
"trimming." (Figure 2F) As the corpora cavernosa (the bodies that fill
with blood to create an erection) develop in adolescence, the penis will
enlarge to "take up the slack."10 A prepuce that in childhood appears long,
may, at maturity, fail to completely cover the glans. A recent study published in the Journal of Urology finds that by ages 8 to 10, fifty percent of
boys will have a fully retractable prepuce.l1
3. BLOOD SUPPLY
5.2. The Mucocutaneous Junction
The blood supply to the prepuce arises from the inferior external
pudendal artery.12 There are four branches of this artery. Two enter the
superficial fascia dorsolaterally (upper sides) and two enter ventrolaterally
(lower sides). These arteries are reflected towards the coronal sulcus where
they anastomose (connect) with collaterals of the dorsal arteries. The blood
supply to the frenulum arises from the dorsal arteries, which at this point
have become dorsolateral13 Venous drainage is accomplished by way of
multiple small veins that join the superficial dorsal veins, which, in turn,
drain into the saphenous vein.
The area where the outer prepuce meets the inner mucosa is known
as the muco- cutaneous junction. Like the junctional regions of the eyelids
and lips, the quantity and specia1isation of nerve endings increase in these
transitional zones.17
4. HISTOLOGY
The mucosa of the inner prepuce is lined by stratified squamous
epithelium, similar to the frictional mucosa of the vagina. As with other
frictional mucosae, such as the lining of the inner eyelid, the mouth, and the
esophagus, the mucosal aspect of the prepuce has a great capacity for selfrepair. The neural and vascular networks of the preputial mucosa rise higher
in the dermis, thereby favouring more acute sensation.14
5.3. Nerve Endings
Numerous specialised nerve endings have been identified in the
prepuce.l3-22 Among them are: paccinian corpuscles (responsible for sensing
pressure); Ruffini's corpuscles (mechanoreceptors); end-bulbs of Krause (most
likely responsible for sensing cold); free nerve endings (pain receptors); and,
perhaps the most important in terms of erogenous sensation, Meissner's
corpuscles, which are sensitive to light touch.
6. ADULT PREPUTIAL MORPHOLOGY
Most of the skin that covers the human body is attached to
underlying structures. The skin covering the eyes and the penis are
exceptions (Figure 3).
5. INNERVATION
The dorsal and lateral aspects of the prepuce are innervated by the
dorsal penile nerve. The ventral prepuce and frenulum are innervated by the
perinea1"nerve.15 The dorsal and perineal nerves are branches of the
pudendal nerve, which derives from the second, third, and fourth sacral
plexus.
5.1. Neonatal Innervation
There is an extensive network of nerves within the prepuce at birth.
Newborns appear to have a higher density of preputial nerves than adults.16
Figure 3: Anatomy of the penis and prepuce.
6.1. The Penile Skin System
The penile skin's proximal (toward the body) point of attachment occurs at
the base of the penile shaft. The skin extends distally covering the shaft,
riding up and over the corona glandis and the glans. At a point, usually near
the distal (away from the body) extremity of the glans, the skin doubles back
under itself. In this area, the skin trans-itions into a mucous membrane,
which runs proximally in contact with the mucous membrane of the glans. It
continues up and over the corona glandis, ultimately finding its
circumferential point of attachment at the coronal sulcus.
6.2. The Preputial Mucosa
The mucosa of the inner prepuce is comprised of two distinct
dermatological zones: the ridged mucosa; and the smooth mucosa.
6.3. The Ridged Mucosa
The ridged mucosa is a pleated band that occurs near the
mucocutaneous junction. It contains 10 to 12 transverse ridges, whose
collective width is 10 to 15cm.23 Clusters of the tactile nerve endings of
Meissner (Meissner's corpuscles) are found in abundance in the crests of
these ridges. They are not present in the sulci (furrows) between the ridges.24
6.4. Smooth Mucosa
The smooth mucosa constitutes the remainder of the inner pre-puce,
from the ridged band to the coronal sulcus.
frenulum, which connects the tongue to the floor of the mouth, frenula
tether movable structures to non-movable structures. The lingual frenulum,
for example, not only prevents the tongue from being swallowed, but also
restricts movement of the tongue in the distal direction. The preputial
frenulum restricts proximal movement of the ridged band and assists in
returning the prepuce to its distal position over the glans.
7. LANGUAGE
Originally, the word prepuce (or foreskin) referred to the skin in
front of the glans penis. In fact, the style of circumcision practised by the
ancient Hebrews until 140 CE involved only the removal of the skin that
protruded beyond the tip of the glans.25 A style of circumcision promoted
in 1917 involved the excision of a large section of the penile shaft skin and
subsequent suturing of the distal and proximal skin remnants.26 Given
individual differences in penile skin length, the ongoing variability in
circumcision techniques, and the ability of the penile skin to change shape
under differing circumstances, it may benefit our understanding of this
penile skin system and facilitate a more accurate means of describing its
physiology if we were to abandon the notion of fore skin and instead view
the penile integument as a continuous sheath.
8. PHYSIOLOGY
The penile skin system is unique in its form and function. No other
part of the human anatomy possesses the ability to evert and invert like the
movable penile skin sheath.
8.1. Protection
6.5. The Frenulum
On the ventral aspect of the glans, the point of attachment of the
prepuce is advanced towards the meatus and forms the frenulum, a bridgelike structure that is continuous with the ridged band. Like the labiogingival
frenulum, which connects the upper lip to the upper gum and the lingual
It has been noted that the prepuce protects the sensitive glans in
infancy, and that this protection lasts throughout life.27 Given the limited
sensitivity of the glans in relation to the highly innervated inner prepuce,28
one could argue that the outer layer of the prepuce protects the inner layer,
while the glans serves the prepuce by giving it form.
The ridged mucosa of the prepuce is so highly vascularised that a
vascular blush is often apparent at this site.29 This high degree of
vascularisation combined with the ability of the dartos fascia to contract and
draw the penis closer to the body in the presence of cold adds another
element of protection.
8.2. Lubrication
The glans penis, like the glans clitoridis, is designed as an internal
organ. This internalisation insures that both the epithelia of the inner
prepuce and the glans remain smooth and moist. This enclosed environment
maintains the suppleness of both of these structures.
8.4. Intercourse
Upon full erection, there is ample play in the penile skin to allow the
glans to glide in and out of the prepuce. During the inward motion of
intercourse (Figure 5), the ridged mucosa, positioned now near the midpenile shaft, glides along and in contact with the vaginal wall. The
Meissner's corpuscles in the crests of the ridged mucosa are stimulated by
this contact and by the restraint of the frenulum, with which the ridged
mucosa is continuous. In the outward motion of intercourse, the prepuce
inverts over the distal portion of the penis. The Meissner's corpuscles are
again stimulated, this time by contact with the corona glandis.
8.3. Erection
Upon erection, the prepuce everts, supplying the penis with ample
integument to accommodate its increased size, while deploying the ridged
mucosa in an oblique circumferential position on the penile shaft (Figure 4).
Figure 4. Eversion of the prepuce upon
erection, with exposure of ridged band along
shaft.
Figure 5. Action of the prepuce in sexual intercourse. Adapted from Ritter TJ, Denniston GC. Say
No to Circumcision! 2nd ed. Aptos:Jurglass. 1996;12-14. Used by permission of the publisher.
9. THE ANATOMICAL AND PHYSIOLOGICAL
CONSEQUENCE OF CIRCUMCISION
Circumcision diminishes the penis, removing approximately half of
the penile skin.30 One study found that the amount of tissue lost to living
adult males ranged from 64 to 90 square centimetres.31
Circumcision results in the excision of both the outer and inner
prepuce. The circumferential line of excision usually occurs near the
coronal sulcus, and in many cases may involve penile shaft skin. In the
United State, the standard techniques of neonatal circumcision almost
always result in the excision of the frenulum. The resultant ablation of the
specialised nerve endings found in these regions irreversibly desensitises the
penis, rendering it incapable of experiencing the full range of sensual and
sexual sensations afforded the intact male.
Circumcision externalises the glans, thereby exposing it to the
abrasive friction of clothing. The inevitable keratinisation, drying, and
callousing of the mucosal lining of the glans further erodes penile
sensitivity.
The unique ability of the penis to glide in and out of itself is
dependent on a complete penile integument. The diminution of this
integument limits or precludes the important role of penile skin mobility in
sexual foreplay.
During sexual intercourse, the penile skin sheath enfolds the distal
portion of the penis, thereby conserving coital lubrication (Figures 5). In the
absence of penile skin mobility, a relatively static structure is created. The
resulting dowel-like penis with its mushroom-shaped head draws lubrication
from the vagina with each outward motion of intercourse, increasing
abrasion and loss of lubrication.
10. CONCLUSION
Historically, certain parts of human anatomy have been deemed redundant
or superfluous. The adenoids, mastoids, and tonsils fell into this category. It
was not until researchers identified the functions of these organs that they
were spared indiscriminate excision, and given their due respect. Even the
appendix, by its very name considered an appendage to the body, is now
known to be part of the immune system, producing large numbers of
lymphocytes.
The fact that routine circumcision in America has become
institutionalised may explain why some people find it difficult to ascribe
any value or function to the prepuce. An overwhelming body of primary
research, however, demonstrates that the prepuce does, in fact, have a
wide range of valuable functions.
The prepuce is not a redundant part of human anatomy. It is, rather,
a complex of specialised erogenous structures that work in sympathy with
adjacent penile structures. It is not a "superfluous tag of skin," as some
would describe it, but a large platform for the reception and expression of
sensual and sexual sensation. The prepuce is not an appendage to the
penis, but a continuum of the specialisation that distinguishes male genital
anatomy.
REFERENCES
1. American Academy of Pediatrics. Newborns: Care of the Uncircumcized [sic] Penis. Evanston:
American Academy of Pediatrics. 1984.
2. See: Snell RS. Atlas of Clinical Anatomy. Boston: Little, Brown and Company. 1978:136.
3. Glenister TW. A consideration of the processes involved in the development of the prepuce in
man. Br J Urol 1956;28:243-9.
4. Hunter RH. Notes on the development of the prepuce. J Anat 1935;70:68-75.
5. Gairdner D. The fate of the foreskin. BMJ 1949;2:1433-7.
6. Gairdner D. The fate of the foreskin. BMJ 1949;2:1433-7.
7. Hunter RH. Notes on the development of the prepuce. J Anat 1935;70:68-75.
8. Jefferson G. The peripenic muscle: some observations on the anatomy of phimosis. Surgery,
Gynecology and Obstetrics 1916;23:177-81.
9. Woolsey G. Applied Surgical Anatomy. New York: Lea Brothers. 1902:405-7.
10. Jefferson G. The peripenic muscle: some observations on the anatomy of phimosis. Surgery,
Gynecology, and Obstetrics 1916;23:177-81.
11. Kayaba H, Tamura H, Kitajima S, Fujiwara Y, Kata T, Kata T. Analysis of shape and
retractability of the prepuce in 603 Japanese boys. J Urol 1996;156:1813-5.
12. Hinman F. The blood supply to preputial island flaps. J Urol 1991;145:1232-5.
13. Juskiewenski S. A study of the arterial blood supply to the penis. Anatomia Clinica 1982;4:1017.
14.
Winkelman RK. The erogenous zones: their nerve supply and its significance. Proceedings of the
Staff Meetings of the Mayo Clinic 1959;34:39-47.
15. Kaneko S. Penile Electrodiagnosis penile peripheral innervation. Urology 1987;30:210--2.
16. Winkelmann RK. The cutaneous innervation of human newborn prepuce. J Invest Dermatol
1956;26:53-67.
17. Winkelman RK. The erogenous zones: their nerve supply and its significance. Proceedings of the
Staff Meetings of the Mayo Clinic 1959;34:39-47.
18. Ghmori D. Uber die Entwicklung der Innervation der Genitalapparate als Peripheren Aufnahmeapparat der Genitalen Reflexe. Zeitschrift far Anatomie und Entwicklungsgeschichte 1924;70:347410.
19. De Girolano A, Cecio A. Contributo alla conoscenza dell'innervazione sensitiva del prepuzio
nell'uomo. Bollettino della Societa Italiana de Biologia Sperimental. 1968;44:1521-2.
20. Winkelmann RK. The cutaneous innervation of human newborn prepuce. J Invest Dermatol
1956;26:53-67.
21. Bazett HT, McGlone B, Williams RG, Lufkin HM. Depth, distribution and probable identification
in the prepuce of sensory end-organs concerned in sensations of temperature; thermometric
conductivity. Archives of Neurology and Psychiatry 1932;27:484-515.
22. Taylor JR, Lockwood AP, Taylor AJ. The prepuce: specialized mucosa of the penis and its loss to
circumcision. Br J Urol 1996;77:291-5.
23. Taylor J. The prepuce: specialized mucosa of the penis and its loss to circumcision. Transcript of
Presentation at the Second International Symposium on Circumcision. May 1, 1991.
24. Taylor JR, Lockwood AP, Taylor AJ. The prepuce: specialized mucosa of the penis and its loss to
circumcision. Br J Urol 1996;77:291-5.
25. Kohler K. Circumcision. In: Jewish Encyclopedia. New York: KTAV Publishing House, Inc.
1964:93.
26. Austin FD, Sharpe TG. Circumcision. New York Medical Journal 1917;106:787-88
27. American Academy of Pediatrics. Newborns: Care of the Uncircumcized [sic] Penis. Evanston:
American Academy of Pediatrics. 1984.
28. Halata Z, Munger BL. The neuroanatomical basis for the protopathic sensibility of the human
glans penis. Brain Res 1986;371:205-30.
29. Taylor JR, Lockwood Ap, Taylor AJ The prepuce: specialized mucosa of the penis and its loss to
circumcision. Br J Urol 1996;77:291-5.
30. Taylor JR, Lockwood AP, Taylor AJ. The prepuce: specialized mucosa of the penis and its loss to
circumcision. Br J Urol 1996;77:291-5.
31. Werker PM, Terng AS, Kon M. The prepuce free flap: Dissection feasibility study and clinical
application of a super-thin new flap. Plast Reconstr Surg 1998;102:1075-82.
The following quote relating to the “circumcision decision” is from an interview
with Dr. John R. Taylor, co-author of
“The prepuce: specialized mucosa of the penis and its loss to circumcision.”
British Journal of Urology 1996;77:291-295.
The prepuce is a structure in its own right
and it has to be given a value before
you make any decision.
This is specialized skin and mucous membrane.
It's built very much like the lips, or the vulva in the female;
it's a junction between skin and the inner lining.
It contains highly specialized nerve endings,
which are only found in a few places in the body,
and we only find this sort of tissue in areas where
it has to perform specialized function,
and this specialized function has to do with sex.
This is sexual tissue,
and there's no way you can avoid the issue.
Most people look at the child and the prepuce,
and say that, well, the prepuce isn't much use for a child.
Well, the prepuce isn't designed for a child,
it's designed for an adult
and you can't look at it in childish terms.
FOR MORE INFORMATION:
www.doctorsopposingcircumcision.org/video/prepuce.html
www.cirp.org/pages/anat/
www.coloradonocirc.org/anatomy
www.cirp.org/library/anatomy/taylor
Fine-touch pressure thresholds in the adult penis
Morris L. Sorrells, James L. Snyder, Mark D. Reiss, Christopher
Eden, Marilyn F. Milos, Norma Wilcox, Robert S. Van Howe. Finetouch pressure thresholds in the adult penis. British Journal of
Urology (BJU) International, April 2007, Volume 99, Issue 4, pages
864-9.
In April 2007, a landmark study was published in the British Journal
of Urology, which demonstrates conclusively that circumcision harms
the sensitivity of the penis. It contains a literature review of other
evidence relating to the effects of circumcision on sexuality. This is
the first study to measure the sensitivity of the foreskin itself
compared to other parts of the penis; previous studies have only
compared the glans of the circumcised penis vs. the glans of the intact
penis. It is also the first to map multiple anatomical points instead of
testing just one point each on the glans or shaft.
CONCLUSIONS: The transitional region from the
external to the internal prepuce is the most sensitive
region of the uncircumcised penis and more sensitive
than the most sensitive region of the circumcised penis.
Circumcision ablates the most sensitive parts of the
penis.
Full study article available for download at:
http://www.nocirc.org/touch-test/bju_6685.pdf
Comparative fine-touch sensitivity of selected regions of the penis
and foreskin (adapted from Semmes-Weinstein testing data in
Sorrells et al., 2007). Taller bars indicate greater fine-touch
sensitivity. The most sensitive parts of the intact penis are missing
from the circumcised penis.
Key:
Light (front bars): circumcised penis
Dark (rear bars): intact penis